(2R,3S,4E)-N-methyl-5-(4′-pentylphenyl)-2-aminopent-4-ene-1,3-diol, also known as SK1-I and BML-258 (as HCl salt), is a pharmaceutical inhibitor of sphingosine kinase 1 initially described in Paugh et al., Blood. 2008 Aug. 15; 112(4): 1382-1391. An existing method for synthesizing SK1-I is disclosed in U.S. Pat. No. 8,314,151.
What is needed and provided by the present invention are improved methods for synthesizing SK1-I and related compounds.